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Rodent of the Week: Chemo disrupts birth of new brain cells

December 18, 2009 | 1:00
pm

Many people refer to something called chemo-brain that occurs while on chemotherapy. The medications, while attacking cancer cells, also seem to affect cognitive function. A new study depicts what happens in the brain from these potent drugs and suggests a method that may help resolve the problem.

Researchers from the University of Rochester Medical Center developed a rodent model to test which among four commonly used chemotherapy drugs crossed the blood-brain barrier. Two medications were known to cross the barrier and two were not expected to do so. But the study showed all four drugs caused a significant breakdown of brain cell regeneration in the animal model, including a 15.4% reduction in new brain cells after use of fluorouracil, a 30.5% reduction following cyclophosphamide, a 22.4% reduction following doxorubicin and a 36% reduction following paclitaxel.

"It could be that all of the chemo drugs cross into the brain after all, or that they act via peripheral mechanisms, such as inflammation, that could open up the blood-brain barrier," the lead author of the study, Dr. Robert Gross, said in a news release.

Previous studies, however, have shown that the experimental growth hormone, IGF-1, may increase the number of new brain cells, which could reduce the cognitive effect of chemotherapy.